Interior radially expanding clutch with equalizing means



Jan. W 195 A. F. BERGER 4 9 9 INTERIOR RADIALLY EXPANDING CLUTCH WITH EQUALIZING MEANS Filed Feb. 14, 1944 .2 Sheets-Sheet l m INVENTOR.

ARNEY.

Jan. 10, 1950 A. F. BERGER INTERIOR RADIALLY EXPANDING CLUTCH WITH EQUALIZING MEANS Filed Feb. 14, 1944 I 2 Sheets-Sheet 2 ATTORNEY Patented Jan. 10, 1950 INTERIOR RADIALLY EXPAND ING CLUTCH WITH EQUALIZING MEANS Arthur F. Berger, Dayton, Ohio, assignor to The Master Electric Company, Dayton, Ohio, a corporation of Ohio Application February 14, 1944, Serial No. 522,250

This invention ertains to mechanically operated clutches, brakes and power control devices, and more particularly to frictional engag ing units of rotary expansion and contraction type.

For illustrative purpose, but without intent to unduly limit its scope or application, the invention is herein illustrated and described as embodied in a centrifugally operated clutch of internal expansion construction, but is not limited thereto.

As heretofore constructed, the frictional shoes of such devices are usually pivotally mounted for oscillatory motion into and out of engaging relation. The frictional contact engagement, of such oscillatory engaging members is ununiform and the engaging pressure is not evenly distributed over the engaged frictional area.

The frictional power unit forming the subject matter hereof is so constructed that the frictional shoes or engaging elements have substantially right line motion into and out of operative relation with the frictional surface of the engaged member. Due to the relatively large area of frictional engaging surface engaged under evenly distributed pressure, the load capacity and effective torque is materially increased.

The object of the invention is to improve the construction as well as the mode of operation of expansive and contractive frictional power transmission units, whereby they may not only be economically manufactured and operated, but will be more eificient in use, automatic in action, uniform in operation, having few operating parts, and be unlikel to get out of repair.

A further object of the invention is to provide an efiicient frictional power unit of compact form and small size with maximum load capacity, wherein the wear of the engaging faces will be uniformly distributed and the life thereof prolonged.

A further object of the invention is to provide a frictional power unit of sufficiently small size and large load capacity to enable it to be conveniently mounted interiorly of a typical electric motor.

A further object of the invention is to provide a frictional unit capable of equally effective operation in either direction of relative rotation.

A further object of the invention is to provide a frictional unit sensitive to fluctuations of speed of rotation and readily responsive to variations of centrifugal influence which will be effective within a prescribed range of speed and load.

A further but nonetheless important object of 14 Claims. (Cl. 19276) the invention is to provide an operating mechanism by which the movement of the frictional engaging members into'and out Of engagement is effected by a substantially straight line equalized movement and their pressures equalized.

A further object of the invention is to provide a frictional power unit of the character herein described, having the advantageous structural features and inherent meritorius characteristics and mode of operation herein set forth.

With the above primary and other incidental objects in view as wil1 more fully appear in the specification, the invention'intended to be protected by Letters Patent consists of the features of construction, the parts and combinations thereof, and the mode of operation, or their equivalents, as hereinafter described or illustrated in the accompanying drawings.

In the drawings, wherein is shown the preferred but obviously not necessarily the only form ,of embodiment of the invention,

Fig. 1 is a side view of an assembled centrifugal clutch unit partly broken away, embodying the present invention.

Fig. 2 is a diametrical sectional view on the line 22 of Fig. 1.

Fig. 3 is an enlarged detail sectional view on line 3-'-3 of Fig. 2.

Fig. 4 is a detail view showing the "present invention applied to a brake unit.

Figs. 5 and 6 are respectively a side elevation and diametrical sectional view of a duplex form of embodiment of the invention.

Fig. '7 is a detail view.

Fig. 8 is a detail view of a modification of the duplex operating means.

Like parts are indicated :by similar characters of reference throughout'the several views.

Referring to Figs. 1, 2 and 3 of the drawings, wherein is illustrated a frictional clutch unit embodying the instant invention, I identifies a laterally recessed drum comprising the driven member having a central hub 2 by which it may be fixedly secured upon a driven shaft. The internal circumferential surface 3 comprises the frictional surface to be intermittently engaged by relatively adjustable friction shoes.

Mounted closely adjacent to the laterally open side of the drum l is a driving member .4, comprising a hub 5 engageable with a driving shaft, or, for example, the rotor of an electric motor, and diametrically opposite peripheral ears 6 supporting pivotal studs '|l upon which the operating parts of the assembly are mounted interiorl of the drum l. Mounted on the studs 1 are'hubs 8 3 having reversely facing diametrically Oppos te the interior of the drum occurs simultaneously shoulders 9 and I I]. Fixedly attached to the pand under uniform pressure throughout the posite ends of the hubs 8 are bifurcated oscillalength of the friction faces I1. tory weight arms II carrying at their free ends By Varying the weights I2 of the arms II the centrifugally influenced weights I2. 5 friction elements may be made to engage and The spaced furcations of the arms II are seated disengage at predetermined speeds. Also, by in terminal rabbets of the hubs and securely adjustment of the weights the frictionally enunited thereto for unison oscillation. os= *gage'e'l sur faces may be caused to slip at a precillatory weight arms II are interconnected for scribed maximum load or resistance, thereby equalized movements by a ring I4 interposed bepreventing the overloading of a driving motor or tween the hub 2 of the driven drum I and the other actuating mechanism. In the event the hub 5 of the driving member ror indepen ent operating levers II should be unevenly weighted, rotative adjustm t. h ng l4 t 'hio'vibld whereby one will tend to swing outwardly quicker at diametrically pp p in s wi h fingers I5 and more forcibly than the other, their operative Which p je t hrou l ed hol'es I5 in the movements will be coordinated and their action p d furcations 0f he Weighted arms II. V The equalihed by" the corresponding rotative adjustns uc i n is su h that the swin i g m t n .ment of the ring 14, by which excessive inertia of one of the weighted arms 'II and its hub tin of one weighted lever will be imparted to the either direction is transmitted to the opposite other lever to insure uniform equal pressures arm I I and hub 8 by a corresponding rotative upon the respective friction shoes.

adjustment of the ring I4 to insure equalized 'The resin-tin straight line adjustment of the rocking movements of the respective hubs 8. friction shoes into operative engagement with ns r r p fera y, but n thec a ily, the *drui'n I"'is quite advantageous in affording formed -integral-ly with the ring by-being stamped evenly distributed pressure throughout the enfrom a single piece of material and bent o pe tire friction area, which affords increased load end ar lati to theiplane f t a ca acit and driving or "braking torque, as the Disposed within the drum I in substantially case may be. Such application :of uniform parallel relation with opposite sectors thereof are evenly distributed pressure minimizes localized arcuate friction shoes Hi, to the outer or convex wear and increases the wearing ability and effecfaces of which are secured strata-I1 -of friction two life of the frictional surfaces. The small material. The shoes I6 are preferably l ngisize and compact construction of the present unit tudinally ribbed or'flanged at -16", Fig. 3,-to-s'tiflen enables it to be incorporated within an "electric the arcuate shoes'and increase their resistance motor housing forpurpose ofconnecting and disto bending strain. The friction material -I I may connecting the motor rotor with the rotor shaft be of anysu-itable character, such as metallic or in accordance with fluctuations of its speed of woven material; or of other character according rotation, whereas former clutches of equivalent to the conditions -of use and work to be perload capacity have necessarily beenof such size formed. The contact faces of the friction suras to preclude such installation. faces of the shoes are contoured to agree with Although the weights I2 are relatively small the interior face 3 of the drum I. one end 'of 40 and the range 'of movement of the swinging-arms each arcuate friction shoe I6 abuts against the quite limited, the construction is such that the shoulder 9 of the rocking hub '8, which is prefcentrifugal influence and movement is amplified erably undercut or recessed at 1-8 to :provide -a to such exten't that the unit will perform the seat therefor. The other end of each arcuate 7 function of a "conventional unit of much greater friction shoe I-Ii is provided with an adjustable size. -Furthermore, the present unit is readily screw threaded stud I9 which seats ln-adepresaccessible for repairs and inspection by merely sion orseat 20 in the face -I'0 of-one of -the-hubs sliding the drum axially of a "driven sh'aft away 8. The adjustment of the screw threaded 'stud from the driver and the entire mechanisn'i is IQ-enableslooseness-or iplay tobeehminatcdand I exposed To permit dust, :grit and foreign inathe assembly rendered accurately responsive to terialto 'readiiy escape,andto affordample ventiminute 'movement'of the weighted arms. lation, 'the 'web'of the drum I is preferably pm- The oppositely disposed reverse shoulders -9 videdwltha-plurality'ofair holes M.

and I0 of the hubs -8' again'st which theends of While the'construction has been described as the opposite friction shoes are engaged in apembodied in *a fricti'onc'lutc'h, for which it is well proximatdy qually spaced relation with *the adapted, substantially the 'same construction,

axis of oscillation of the hub and 'connected fromwhich theweighte'd a ms bare Omitted,

arm affords le'verageby which upon outwardly maybe :utilized as a brake unit, illustrated in swinging movement of the "corresponding arm Fig. 4. in this construction the hubs 8 carry t armor one friction-shoe I6 is forced laterally Spaced'arms 22, having therein holes Hi inwhich in one direction and that of the other shoe is the/fingers 1 5 ofth'e equalizing ring 14 engages forced in the opposite direction. The Opposite to transmit rocking motion uniformly from one ends the respective Shoes rs being engaged hub to the other. Adjustment of "an oscillatory in like manner t t t r of the hubs 8 -re brake lever d sconnected with one of the hubs 8, ceive like outward lever-age influence, by'similar the movement of which is -'t'ransmi tted from one rotation of the other 'hub. The rotati-veadjust- 6B hubto theother by the rih'g reserves t'o-adjust ment of the respective hubs 8 and correspo'ndthe friction shoes into frictional engagem ttw' 't ing reverse movements of therends ofthe =ar'-' the-interior' face 3 'of the drum proportionately to cuate friction shoes are equalized by 'the ring the-po i p tt 't j I 4' which interconnects the weighted levers I I. y In Figsrbhiid-G is shown'aduplex'arrangement The separating influence exerted upo'nthe a rof the clutch construction heretofore described, cuate friction shoes being'equal at their oppos'ite wherein substantially the'same elements'are emends, the shoes are moved-apart-and 'iifto con-tact played, but the friction shoes are separately o'pengagement with the interior face -3 -'of the drum' erated and relativ'eadjustmentenabled. In such I insubstantially 'straight lines. As a-i-es'ult -the' embodimeift the asselnblybf 'the driven drum I frictional engagement of the surfaces 1"] with 75afixd to a sliaft byitshub 2and associatedwith .-the driving member 4, provided with. thehub .5

engageable with a drive shaft or the like, and radially disposed ears or lugs 6 carrying the pivotal studs 1, is substantially as shown in the preceding figures of the drawing and heretofore described. Journalecl on the hub 5 of the driving member or spider 4 for limited oscillatory adjustment is a collar 24 having diametrically disposed ears or lugs 25 agreeing with the ears or lugs 6 of the driver 4. The collar is secured against displacement by a lock ring 26 seated in a peripheral groove in the hub 5. The cars or lugs 25 of the auxiliary collar 24 carrying studs or pins 21, which correspond to the pivotal studs 1 carried by the member 4.

Journaled on studs 1 and 21 of the respective members 4 and 24 are hubs 8' and 8", having at their outer sides shoulders9 undercut as at l8 to receive the ends of the friction shoes l6, both extremities of which in this instance are flat. Each of the friction shoes it engages at one end with the shoulder 9 of a hub 8' carried by the main drive member 4 and at its opposite end with a like shoulder 9 of a hub 8" carried by an ear or lug 25 of the auxiliary collar 24. The hubs 8 and 8" are interconnected in pairs for unison rotative motion in opposite directions by a short flexible strip or link 28. The ends 29 of the coupling link 28 are angularly bent in opposite directions for engagement in notches 30 in the hubs 8 and 8" in relatively spaced relation with the friction shoe seats 9. The flexible coupling strip 28 extends between the hubs 88 and follows in reverse curvilinear directions the peripheries of the respective hubs. The movement of a hub 8' by the action of the weighted arm II connected thereto istransmitted in reverse direction to the corresponding hub 8" by such coupling strip. The reversely bent ends of the strip are hooked in the notches, where they may be secured in any suitable manner. One method of 'locking the coupling strip ends, as shown in Fig. 7, consists in inserting a wedge 3! in the notch 30 alongside of the bent end 29 of the strip, and holding the wedge in clamping relation by the overhanging head of an adjusting screw 32. The oscillatory weighted arms H are connected with the hubs 8' and are interconnected and their movements are equalized by the ring l4 as before described. The oscillatory motion of the weighted arms H effects rocking motion of the hubs 8' to simultaneously adjust one endof each brake shoe connected with the respective hubs 8'. The rocking motion of the hubs 8 is transmitted to like degree by the coupling strips 28 to the hubs 8", with which the opposite ends of the friction shoes are engaged. Thus, one end of each friction shoe is adjusted by the rocking motion of one of the hubs 8', under direct influence of one weighted arm I I, while the opposite end of the same shoe is simultaneously adjusted to like extent by rocking motion of one of the hubs 3', to which motion is transmitted from the mating hub 8' under infiuence of the other weighted arm I I by the coupling strip 28. By rotative adjustment of the collar 24 and its associated hubs 8" relative to the member 4 and the primary hubs 8, the range of movement of the friction shoes relative to the drum may be varied and wear or lost motion may be compensated. Such adjustment of the rela-' tively rotative parts 4 and 24 is preferably effected by a screw 33. In Fig. 5 the friction material I! is shown applied to the interior of the drum, where it is continuous and may be engaged by the shoes in any position of relative rotative ad justment. Thismaterially increases the frictiom a] contact surface and distributes the wear, thus materially increasing the period of effective operation of the unit. 7 Such application of thefriction material to the drum may be utilized in the primary construction illustrated in Figs. 1 to 4, as well asin the embodiment of Figs. 5 and 6.

In Fig. 8 there is shown a modification wherein thrust members 8a and 8b analogous to the thrust members 8' and 8" of Fig. '7 are journaled upon the studs 1 and 21 of the respective members 4 and 24, as before described. These thrust members also have shoulders 9 undercut as at. I 8 to receive the ends of the friction shoes is, instead of being connected by the strap 28 for unison oscillation in opposite directions, as before described. These thrust members 8a and 8b are provided with interengaging radial arms 34, which cooperate somewhat in the manner of spur gear teeth whereby a partial rotation of one member will effect a like partial rotation of the other member to like degree. By such unison oscillatory motion outward thrust upon the friction shoes is exerted and relaxed in unison and to like degree. The oscillatory motion of one weighted arm is transmitted to one oscillatory thrust mam,- ber 8a or 812 of each pair thereof and the motion of such member is transmitted to the other. It will be understood that there are provided two pairs of the thrust members 841 and 81) at diametrically opposite points as is shown in Fig. 5, each pair being under direct influence of one weighted arm orother actuating device. The respective weighted arms and the pairs of oscillatory thrust members are intercoupled for unison action by the equalizing ring !4, as before described.

From the above description it will be apparent that there is thus provided a device of the character described possessing the particular features of advantage before enumerated as desirable, butwhich obviously is susceptible of modification in its form, proportions, detail construction and arrangement of parts without departing from the principle involved or sacrificing any of its advantages.

While in order to comply with the statute the invention has been described in language more or less specific as to structural features, it is to be understood that the invention is not limited to the specific features shown, but that the means and construction herein disclosed comprise the preferred form of several modes of putting the invention into effect, and the invention is therefore claimed in any of its forms or modifications within the legitimate and valid scope of the appended claims.

Having thus described my invention, I claim: 1. An expansive and contractive frictional unit, including driving and driven'members, a pair of reversely disposed arcuate frictional shoes carried by one member and movable in unison into and out of frictional engagement with the other member, recessed oscillatory thrust ele ments carried by one of said members interposed between the adjacent ends of the arcuate fric-. tion shoes which are seated withinthe recesses and upon oscillation exertin simultaneous outward thrust pressure of the shoes into frictional engagement with the other of said members, fixed pivots carried by said member upon which the thrust elements are supported for oscillatory movement, and an equalizing ring interconnect ing the oscillatory thrust membersand rotatable ing members for the frictional shoes interposed between the opposite adjacent ends thereof, recessed bearing seats on said oscillatory members in radially spaced relation with their axes of oscillation engaged by the ends of the arcuate friction shoes and exerting thrust pressure in opposite directions thereon upon oscillation of said oscillatory members, means for actuating at least one of the members, and equalizing means maintaining uniform degree of oscillatory motion of the members intermediate the opposite ends of the arcuate frictional shoes. v

12. A frictional power unit wherein a pair of reversely disposed arcuate frictional shoes are intermittently engageable simultaneously with the interior surface of a surrounding annular frictional member, including oscillatory supporting members interposed between the contiguous inturned opposite ends thereof, relatively mov able seating areas thereon in which the ends of the opposite ends of the arcuate shoes are supported, and actuating means for uniformly oscillating the supports to effect unison uniform movement of the arcuate shoes throughout their lengths through straight line paths.

13. A frictional power unit wherein a pair of reversely disposed arcuate frictional shoes are intermittently engageable simultaneously with the interior surface of a surrounding annular frictional member, including movable supporting members interposed between the adjacent opposite ends thereof, shoe receiving seats therein within which the opposite ends of the frictional shoes are supported, actuating means for simultaneously moving the shoe receiving seats therein through substantially straight line movement of limited extent to separate the ends of one shoe from the ends of the other, and an equalizer maintaining the degree of separation of the opposite ends of the shoes uniform.

14. A frictional power unit wherein a pair of reversely disposed arcuate frictional shoes are intermittently engageable simultaneously with the interior surface of a surrounding annular frictional member, a pair of oscillatory thrust members interconnected for unison oscillation interposed between the adjacent ends of the arcuate frictional shoes, thrust seats on each of the thrust members engaged by the end of the corresponding arcuate shoe, means for actuating at least one oscillatory member of one of the pairs thereof, equalizing means for limiting the degree of oscillation of the members of one pair to that of the other pair, the construction and arrangement being such that the frictional shoes are simultaneously actuated through substantially straight line movement uniformly throughout their lengths into contact engagement with the surrounding annular member.

ARTHUR F. BERGER.

REFERENCES CITED The following references are of record in the file of this patent: 

